PG Gas Field Well Test Interpretation Model And Application Research

Well test technology is one of the important means of knowning gas reservoirs, conducting gas reservoir evaluation and production performance observation. For the formation characteristic and development situation of PG gas field, this paper set up and solved three kinds of well testing models respectively, they are dual-porosity model, composite model and multilayed model. Furthermore, the characteristics and influential factors of the dual-logarithm curves were analyzed. On this basis, this paper interpreted factual well test data of PG gas field.The main research content includes:(1)A dual-porosity model has been built, and this model considered many factors,such as, phase seperation, well-bore storage effect and skin effect and so on.The Laplace solutions of non-dimensional bottom hole pseudopressure of infinite boundary, outer sealed boundary and constant pressure outer boundary have been obtained. And this paper has also analyzed the characteristics and influential factors of the dual-logarithm curves.(2)A two-zone compund well test interpretation mathmatical model for high sulfur-bearing gas reservoir with homosphere has been built and solved.The dual-logarithm curves of non-dimensional bottom hole pseudopressure of infinite boundary, outer sealed boundary and constant pressure outer boundary have been obtained by the application of Stefest an Matlab. And this paper has also analyzed the characteristics and influential factors of the dual-logarithm curves.(3)A two-zone compund well test interpretation mathmatical model for high sulfur-bearing gas reservoir with dual-porosity media has been built. The Laplace solution of non-dimensional bottom hole pseudopressure of infinite boundary has been obtained. The dual-logarithm curve of non-dimensional bottom hole pseudopressure of infinite boundary has been obtained by the application of Stefest an Matlab. And this paper has also analyzed the curves' characteristics and the effect of parameters such as sulfur saturation and mobility ratio on the dual-logarithm curves.(4)A muiltilayed models without crossflow and a two-layer model with crossflow have been built and solved, and this model considered the factor of phase seperation. The dual-logarithm curve of non-dimensional bottom hole pseudopressure has been obtained by the application of Stefest an Matlab. And this paper has also analyzed the curves' characteristics and the effect of parameters such as storativity ratio and interporosity flow coefficient on the dual-logarithm curves.(5)At last, guided by the theory research, this paper has interpreted factual well test data ofPG gas field.Through the study of dual-porosity model, composite model and multilayed model, we can know characteristics and flow dynamic of PG gas reservoir better. Then, we can guide the development of the gas field better.